Perivascular epithelioid cell tumors (PEComas) are unusual mesenchymal neoplasms composed of histologically and immunohistochemically distinct perivascular epithelioid cells (PECs). Although PEComas have the potential to behave in a malignant fashion, malignant PEComas arising from the retroperitoneum are extremely rare. A 68-year-old woman presented with a painful palpable mass in her left upper abdomen. Computed tomography of the abdomen showed a 9 cm sized heterogeneous mass in left para-aortic space and multiple hypervascular nodules in the liver. 18F-fludeoxyglucose-PET/CT showed multifocal hypermetabolic lesions in retroperitoneum, liver, and skeletal bones. Percutaneous needle biopsies were done on the retroperitoneal and hepatic mass. Both specimens were positive for human melanoma black-45 (HMB-45) on histological and immunohistochemical staining which was compatible with PEComas. Herein, we report a rare case of retroperitoneal PEComa with multiple metastases involving liver and bone at initial diagnosis that exhibited aggressive behavior and resulted in a devastating prognosis.
Aged ; Bone Neoplasms/pathology/radiography/secondary ; Female ; Fluorodeoxyglucose F18 ; Humans ; Liver Neoplasms/pathology/radiography/secondary ; Perivascular Epithelioid Cell Neoplasms/*diagnosis/pathology ; Positron-Emission Tomography ; Tomography, X-Ray Computed

Patellar metastases are very rare. There have been approximately 20 cases reported in the literature. We have also noted two other reports of patellar metastasis from lung carcinoma as the first manifestation of lung cancer in our literature review. We present a case of patellar metastasis as the first manifestation of lung epidermoid carcinoma in a patient who was a smoker for 33 years.
Arthrography ; Bone Neoplasms/secondary* ; Bone Neoplasms/radiography ; Bone Neoplasms/pathology ; Carcinoma, Squamous Cell/secondary* ; Carcinoma, Squamous Cell/radiography ; Carcinoma, Squamous Cell/pathology ; Case Report ; Human ; Lung Neoplasms/radiography* ; Male ; Middle Age ; Patella* ; Radiography, Thoracic ; Tomography, X-Ray Computed

Solitary metastases from colorectal carcinoma in the absence of hepatic or pulmonary metastases are rare. These can have a diverse imaging appearance, particularly after chemotherapy. It is important identify patients with solitary skeletal metastases, as they have a better prognosis than those with multiple skeletal or visceral metastases. We describe an unusual case of a solitary metastasis to the femur in a case of colon carcinoma that went undiagnosed and later presented with imaging features of osteogenic sarcoma.
Adult ; Bone Neoplasms/diagnosis/radiography/secondary ; Carcinoma/*diagnosis/pathology/radiography ; Colorectal Neoplasms/*diagnosis/pathology/radiography ; Female ; Femur/radiography ; Humans ; Magnetic Resonance Imaging ; Prognosis ; Tomography, X-Ray Computed

We report an unusual case of osteoblastic metastasis from gastric carcinoma. In this case, bone metastasis was the initial manifestation of the cancer. The laboratory findings revealed mild hypocalcemia and markedly elevated alkaline phosphatase levels. Plain X-ray showed mottled osteoblastic changes in the pelvis. Bone marrow and bone biopsy of the pelvis revealed metastatic adenocarcinoma with increased osteoblastic activity. An extensive search for the primary site revealed advanced gastric carcinoma, which was confirmed by endoscopic biopsy.
Adenocarcinoma/diagnosis/*secondary ; Adult ; Bone Neoplasms/*diagnosis/pathology/*secondary ; Case Report ; Female ; Human ; *Osteoblasts/radiography ; *Pelvis/radiography ; Radionuclide Imaging ; Stomach Neoplasms/*diagnosis ; Tomography, X-Ray Computed

We report an unusual case of osteoblastic metastasis from gastric carcinoma. In this case, bone metastasis was the initial manifestation of the cancer. The laboratory findings revealed mild hypocalcemia and markedly elevated alkaline phosphatase levels. Plain X-ray showed mottled osteoblastic changes in the pelvis. Bone marrow and bone biopsy of the pelvis revealed metastatic adenocarcinoma with increased osteoblastic activity. An extensive search for the primary site revealed advanced gastric carcinoma, which was confirmed by endoscopic biopsy.
Adenocarcinoma/diagnosis/*secondary ; Adult ; Bone Neoplasms/*diagnosis/pathology/*secondary ; Case Report ; Female ; Human ; *Osteoblasts/radiography ; *Pelvis/radiography ; Radionuclide Imaging ; Stomach Neoplasms/*diagnosis ; Tomography, X-Ray Computed

A case of Wilms' tumor in a 67 year-old female is presented. The tumor totally replaced the left kidney with extension to Gerota's fascia, the adrenal gland and ureter, with tumor thrombi in the left renal vein. Multiple bony metastases to the skull, shoulder, rib, ilium, acetabulum and femur were noted also. Microscopically, the tumor was composed predominantly of blastemal tissue with diffuse anaplasia with areas of tubular differentiation and chondroid elements. Clear cell nests were found in the proximal ureter with gradual maturation downward.
Aged ; Bone Neoplasms/secondary ; Case Report ; Female ; Human ; Kidney/pathology ; Kidney Neoplasms/*pathology/radiography ; Nephroblastoma/*pathology/radiography ; Tomography, X-Ray Computed ; Ureter/pathology

Bone Neoplasms ; diagnostic imaging ; pathology ; secondary ; surgery ; Chondrosarcoma ; diagnostic imaging ; pathology ; secondary ; surgery ; Fingers ; Humans ; Male ; Middle Aged ; Osteochondroma ; pathology ; Radiography

Malignant kidney neoplasms are the most frequently encountered solid kidney masses. Although renal cell carcinoma is the major renal malignancy, other solid malignant renal masses should be considered in the differential diagnosis of solid renal masses that do not contain a macroscopic fatty component. In this pictorial essay, we present the imaging findings of a primitive neuroectodermal tumor, primary liposarcoma of the kidney, primary neuroendocrine tumor, leiomyosarcoma, synovial sarcoma, malignant fibrous histiocytoma, sclerosing fibrosarcoma and renal metastasis of osteosarcoma.
Bone Neoplasms/secondary ; Carcinoma, Renal Cell/pathology/radiography ; Diagnosis, Differential ; Fibrosarcoma/radiography ; Histiocytoma/radiography ; Humans ; Kidney Neoplasms/*pathology/radiography ; Leiomyosarcoma/pathology/radiography ; Magnetic Resonance Imaging ; Middle Aged ; Neuroectodermal Tumors, Primitive/pathology/radiography ; Osteosarcoma/pathology ; Sarcoma ; Sarcoma, Synovial/radiography ; Tomography, X-Ray Computed

OBJECTIVE: The aim of the study was to compare the diagnostic performances of F-18 sodium fluoride positron emission tomography/computed tomography (bone PET/CT) and bone scintigraphy (BS) for the detection of thyroid cancer bone metastasis. MATERIALS AND METHODS: We retrospectively enrolled 6 thyroid cancer patients (age = 44.7 ± 9.8 years, M:F = 1:5, papillary:follicular = 2:4) with suspected bone metastatic lesions in the whole body iodine scintigraphy or BS, who subsequently underwent bone PET/CT. Pathologic diagnosis was conducted for 4 lesions of 4 patients. RESULTS: Of the 17 suspected bone lesions, 10 were metastatic and 7 benign. Compared to BS, bone PET/CT exhibited superior sensitivity (10/10 = 100% vs. 2/10 = 20%, p = 0.008), and accuracy (14/17 = 82.4% vs. 7/17 = 41.2%, p < 0.025). The specificity (4/7 = 57.1%) of bone PET/CT was not significantly different from that of BS (5/7 = 71.4%, p > 0.05). CONCLUSION: Bone PET/CT may be more sensitive and accurate than BS for the detection of thyroid cancer bone metastasis.
Adult ; Bone Neoplasms/*radiography/secondary ; Bone and Bones/*radiography ; Contrast Media/*chemistry ; Female ; Fluorine Radioisotopes/chemistry ; Humans ; Male ; Middle Aged ; Positron-Emission Tomography ; Retrospective Studies ; Sodium Fluoride/*chemistry ; Thyroid Neoplasms/*pathology ; Tomography, X-Ray Computed ; Whole Body Imaging

Alveolar soft part sarcoma (ASPS) is a rare malignant soft-tissue neoplasm of unknown histogenesis. The two main sites of occurrence are the lower extremities in adults and the head and neck in children. We report the first case of pleural ASPS occurring in a 58-yr-old man who presented with progressive dyspnea. A computed tomographic scan of the thorax revealed a large enhancing pleural mass with pleural effusion in the left hemithorax. Wide excision of the pleural mass was performed. Histologically, the tumor consisted of organoid nests of large polygonal cells, the cytoplasm of which had eosinophilic and D-PAS positive granules. Immunohistochemical staining showed that the tumor cell nuclei were positive for transcription factor 3 (TFE3). The pleural ASPS with multiple bone metastases recurred 1 yr after surgery and the patient died of acute pulmonary embolism 1.5 yr after diagnosis.
Bone Neoplasms/diagnosis/secondary ; Dyspnea/etiology ; Humans ; Immunohistochemistry ; Male ; Middle Aged ; Pleura/physiopathology ; Positron-Emission Tomography and Computed Tomography ; Pulmonary Embolism/diagnosis ; Sarcoma, Alveolar Soft Part/*diagnosis/pathology/radiography ; Soft Tissue Neoplasms/*diagnosis/pathology/radiography ; Transcription Factor 3/metabolism